diff options
| -rw-r--r-- | Documentation/devicetree/bindings/serial/snps-dw-apb-uart.txt | 16 | ||||
| -rw-r--r-- | drivers/tty/serial/8250/8250_dw.c | 32 |
2 files changed, 48 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/serial/snps-dw-apb-uart.txt b/Documentation/devicetree/bindings/serial/snps-dw-apb-uart.txt index 7f76214f728a..289c40ed7470 100644 --- a/Documentation/devicetree/bindings/serial/snps-dw-apb-uart.txt +++ b/Documentation/devicetree/bindings/serial/snps-dw-apb-uart.txt @@ -21,6 +21,18 @@ Optional properties: - reg-io-width : the size (in bytes) of the IO accesses that should be performed on the device. If this property is not present then single byte accesses are used. +- dcd-override : Override the DCD modem status signal. This signal will always + be reported as active instead of being obtained from the modem status + register. Define this if your serial port does not use this pin. +- dsr-override : Override the DTS modem status signal. This signal will always + be reported as active instead of being obtained from the modem status + register. Define this if your serial port does not use this pin. +- cts-override : Override the CTS modem status signal. This signal will always + be reported as active instead of being obtained from the modem status + register. Define this if your serial port does not use this pin. +- ri-override : Override the RI modem status signal. This signal will always be + reported as inactive instead of being obtained from the modem status register. + Define this if your serial port does not use this pin. Example: @@ -31,6 +43,10 @@ Example: interrupts = <10>; reg-shift = <2>; reg-io-width = <4>; + dcd-override; + dsr-override; + cts-override; + ri-override; }; Example with one clock: diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c index e60116235836..2ab229ddee38 100644 --- a/drivers/tty/serial/8250/8250_dw.c +++ b/drivers/tty/serial/8250/8250_dw.c @@ -59,6 +59,8 @@ struct dw8250_data { u8 usr_reg; int last_mcr; int line; + int msr_mask_on; + int msr_mask_off; struct clk *clk; struct clk *pclk; struct reset_control *rst; @@ -81,6 +83,12 @@ static inline int dw8250_modify_msr(struct uart_port *p, int offset, int value) value &= ~UART_MSR_DCTS; } + /* Override any modem control signals if needed */ + if (offset == UART_MSR) { + value |= d->msr_mask_on; + value &= ~d->msr_mask_off; + } + return value; } @@ -334,6 +342,30 @@ static int dw8250_probe_of(struct uart_port *p, if (id >= 0) p->line = id; + if (of_property_read_bool(np, "dcd-override")) { + /* Always report DCD as active */ + data->msr_mask_on |= UART_MSR_DCD; + data->msr_mask_off |= UART_MSR_DDCD; + } + + if (of_property_read_bool(np, "dsr-override")) { + /* Always report DSR as active */ + data->msr_mask_on |= UART_MSR_DSR; + data->msr_mask_off |= UART_MSR_DDSR; + } + + if (of_property_read_bool(np, "cts-override")) { + /* Always report DSR as active */ + data->msr_mask_on |= UART_MSR_DSR; + data->msr_mask_off |= UART_MSR_DDSR; + } + + if (of_property_read_bool(np, "ri-override")) { + /* Always report Ring indicator as inactive */ + data->msr_mask_off |= UART_MSR_RI; + data->msr_mask_off |= UART_MSR_TERI; + } + /* clock got configured through clk api, all done */ if (p->uartclk) return 0; |